1. Field of Invention
The present invention relates to a device for locking a lever for pivoting a valve.
2. Related Prior Art
Referring to FIGS. 5 and 6, a valve (not shown) is contained in a valve housing 50. A lever 60 is attached to the valve by means of a shaft 62. By means of the shaft 62, the lever 60 pivots the valve in order to open/close the valve housing 50. In a closed position of the lever 60, a length of the lever 60 is perpendicular to the axis of the valve housing 50 such that the valve closes the valve housing 50. In an open position of the lever 60, the length of the lever 60 is parallel to the axis of the valve housing 50 such that the valve opens the valve housing 50.
Very often, it is desired to maintain the lever 60 in the open position. A conventional device for locking the lever 60 is illustrated. The conventional device for locking the lever 60 has a block 61 formed on the underside of the lever 60 and an elastic strip 70 attached on the valve housing 50. The block 61 is pivotable about the shaft 62 together with the lever 60 as it is formed on the underside of the lever 60. The elastic strip 70 has a U-shaped form (when seen in a top view) defining a cutout 71 and between a first terminal portion 72 and a second terminal portion 73. The second terminal portion 73 is attached to the valve housing 50 in such a way that the second terminal portion 73 is in a higher position than the first terminal portion 72. The first portion 72 has a first edge and a second edge. Normally, the first edge of the first portion 72 is in a lower position than the second edge of the first portion 72.
Normally, the first edge of the first portion 72 is in a lower position than the bottom of the block 61 so that the block 61 is permitted to slide on the first portion 72 when the lever 60 pivots together with the block 61. The block 61 then bypasses the first terminal portion 72 so as to enter the cutout 71. At that instant, the elastic strip assumes the original form so that the block 61 is trapped in the cutout 71 by means of the first terminal portion 72. That is, the lever 60 is retained in the open position.
The lever 60 can be released from the open position only when the terminal portion 72 is pressed downward so that the second edge thereof is below the bottom of the block 61 and that the block 61 is permitted to slide on the first terminal portion 72. The locking device can only be released by using two hands, one for pressing the first terminal portion 72 and the remaining for pivoting the lever 62. This is inconvenient. Furthermore, hands may be easily cut by means of the elastic strip 70 as the elastic strip 70 is generally made of metal.
Therefore, the present invention is intended to solve the above-mentioned problems.